A 17-point scheme and its numerical implementation for high-accuracy modeling of frequency-domain acoustic equation

Frequency-domain modeling is the basis of frequency-domain full waveform inversion. The classical optimal 9-point scheme is only of second-order accuracy, and does not meet the need of high-accuracy seismic imaging. This paper deals with two fourth-order schemes, namely fourth-order 9-point scheme and optimized 17-point scheme. The 17-point scheme reduces the number of grid points required by the shortest wavelength to 2. 56. We also perform numerical tests on a simple model and the Overthrust model, and the modeling results with the three schemes are compared. The results demonstrate the superiority of the 17-point scheme over the fourth-order 9-point scheme and optimal 9-point scheme in terms of reducing dispersion errors. Numerical tests on complex model further confirm the feasibility of the 17-point scheme.